S_OutControl output

Output signal of the safety-related function block (enable signal).

Data type: SAFEBOOL

The enable signal of the function block is the safety-related acknowledge signal for the process to be controlled. It either controls the output of a safety-related device directly or serves as input signal for another safety-related function block.

Its value depends on the status of the upstream safety-related function and the status of the request signal from the standard controller (operation start/stop) as well as the start-up/restart inhibit.

The S_OutControl output signal also controls the request for the stop function.

NOTE:

As the enable signal is present at the S_OutControl output, this output is also called enable output.

Connection: Connect the S_OutControl output to your application as single-channel or two-channel, either directly or via other safety-related functions/function blocks. For this purpose, observe the Notes on backreadable outputs.

The enable signal may only control the process directly if this does not adversely affect the safety-related function.

 WARNING

UNINTENDED EQUIPMENT OPERATION

  • Verify that the enable signal only controls the process directly if this does not adversely affect the safety-related function.

  • Validate the overall safety-related function, including the start-up behavior of the process, and thoroughly test the application.

Failure to follow these instructions can result in death, serious injury, or equipment damage.

Value

Description

SAFETRUE

No safety-related function is requested (normal operation).

The following conditions must be met:

  • The function block has been activated (input Activate = TRUE)

  • and the function block did not detect a triggered safety-related function (input S_SafeControl = SAFETRUE)

  • and no start-up/restart inhibit is active (setting made with S_StartReset and/or S_AutoReset)

  • and running operation is requested (ProcessControl = TRUE)

  • and the function block has not detected an error.

SAFEFALSE

The safety-related function is requested.

This may be due to one of the following reasons:

  • The function block is not activated (input Activate = FALSE)

  • or a triggered safety-related function was detected by the function block (input S_SafeControl = SAFEFALSE)

  • or a start-up inhibit/restart is active (setting made with S_StartReset and/or S_AutoReset)

  • or an operation stop of the standard controller is requested (ProcessControl = FALSE)

  • or the function block has detected an error.

The risk of unintended start-up/restart and/or manipulation can be reduced by combining a stop request from the safety-related application and an operation stop from the standard application.

 WARNING

UNINTENDED START-UP

  • Make certain that appropriate procedures and measures (according to applicable sector standards) have been established to help avoid hazardous situations when starting up the Safety Logic Controller.

  • Make certain that no unintended start-up/restart or manipulation can occur.

  • Validate the overall safety-related function, including the start-up/restart behavior of the process, and thoroughly test the application.

Failure to follow these instructions can result in death, serious injury, or equipment damage.

Precise details of the behavior of the S_OutControl output in relation to the start-up/restart inhibit are given in the following table:

NOTE:

With StaticControl = FALSE you must always consider the optionally additional operation start/stop from the standard application.

Formal parameter

Value

Action

Start-up/restart inhibit

Reset

Enable output

S_StartReset

SAFETRUE

After function block activation/Safety Logic Controller start-up, the start-up inhibit is ...

not active

No action is required at Reset, ...

  • to switch the S_OutControl enable output to SAFETRUE with a valid input signal combination.

  • to exit the start-up/restart inhibit.

SAFEFALSE

active

Reset must be switched from FALSE to TRUE, ...

S_AutoReset

SAFETRUE

After the SAFETRUE signal has returned at the safety-related S_SafeControl input, the restart inhibit is

not active

No action is required at Reset, ...

SAFEFALSE

active

Reset must be switched from FALSE to TRUE, ...

Backreadable outputs: Control at SF_EDM

The function block may only directly control a subsequent safety-related output in the application in case of non-backreadable device outputs. An application example for this can be found in the overview for this function block.

In case of backreadable outputs, you must connect the S_OutControl enable output with the safety-related output in the application via the SF_EDM function block. Refer to the second application example.